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MX

definition

What is an MX record?

An MX record, also known as a Mail Exchange record, is a type of DNS (Domain Name System) record that is used to specify the mail servers responsible for receiving and handling email messages on behalf of a domain. In other words, MX records help direct email traffic to the appropriate mail servers for a particular domain.

When someone sends an email to an address within a specific domain (e.g., user@example.com), the sender’s email server queries the DNS to find the MX records associated with the recipient’s domain (example.com). The MX records contain information about the mail servers that are configured to accept incoming email messages for that domain. These mail servers are prioritized using a priority value, allowing for multiple servers to be listed in case one is unavailable. The sender’s email server then attempts to deliver the email to the highest-priority mail server first. If that server is unavailable, the sender’s server will try the next highest-priority server listed in the MX records.

Each MX record typically includes two main components:

  1. Priority: This is a numerical value assigned to each mail server listed in the MX records. The lowest value corresponds to the highest priority. When delivering an email, the sending server starts by attempting to deliver the message to the server with the lowest priority (highest numerical value). If that server is unavailable, it moves on to the next priority.
  2. Mail Server Hostname: This is the domain name of the mail server responsible for receiving emails for the domain. It’s the address to which the sender’s server will attempt to connect to deliver the email.

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